The molecular functions of fatty acid binding proteins (FABPs) remain obscure nearly 35 years after their discovery. Recent studies with knock-out mice indicate that FABPs play critical roles in the development of the metabolic syndrome and certain cancers making them potential therapeutic targets for these diseases. Specifically, the adipocyte FABP (A-FABP) has been linked to insulin resistance, atherosclerosis, and fatty liver disease. Inhibition of fatty acid binding to A-FABP should provide a useful method to investigate the molecular functions that underlie its observed effects on metabolism, but no inhibitors of A-FABP binding are currently available. To address this need, a high throughput screening (HTS) assay will be developed to discover specific inhibitors of A-FABP binding using a fluorescently labeled A-FABP. The aims of this project are to (1) optimize the A-FABP probe for HTS and (2) screen a small molecular library to validate the effectiveness of the assay for the identification of specific inhibitors of A-FABP binding. To accomplish these aims, the conditions of the A-FABP assay will be varied to optimize the Z'-factor, rapid secondary screens will be developed to identify optical artifacts that alter the observed fluorescence and to confirm binding to A-FABP, and screening results will be assessed by quantitative determination of inhibitor / FABP binding affinities and membrane permeability. Effective inhibitors will be used in a follow-up research program to study the molecular functions of FABPs in lipid metabolism and could lead to the development of therapeutic agents for such diseases as type II diabetes, coronary artery disease, and certain forms of cancer. Recent studies indicate that adipocyte fatty acid binding protein (A-FABP) plays a critical role in insulin resistance, atherosclerosis, and fatty liver disease. Inhibition of fatty acid binding to A-FABP should provide a useful method to investigate the molecular functions that underlie its observed effects on metabolism, but no inhibitors of A-FABP binding are currently available. To address this need, a high throughput screening assay will be developed to discover specific A-FABP inhibitors that can be used to study A-FABP function and may serve as therapeutic leads for the treatment of type II diabetes and coronary artery disease. [unreadable]